Asymmetric synthesis of unusual amino acid: Synthesis of four isomers of β-methyl-3-(2′-naphthyl)alanine

Asymmetric Synthesis of Non-Natural Amino Acid Derivatives: (2R/3S) and (2S/3R) 2-(Tert-Butoxycarbonylamino)-3-Cyclohexyl-3-Phenyl Propanoic Acids

Highly conformationally-constrained novel α-amino acid derivatives ((2R/3S) and (2S/3R)-2-(tert-butoxycarbonylamino)-3-cyclohexyl-3-phenylpropanoic acids) have been synthesised with high stereoselectivity (> 90% de) and in 36–37% overall yields. In the synthesis, Evans’ auxiliary (4(R/S)-4-phenyl-oxzaolidin-2-one) was used to control the stereoselectivity via the key reactions of asymmetric Michael addition, azidation and catalytic hydrogenolysis.

Asymmetric synthesis of chiral 4-substituted 5,5-diethyl oxazolidin-2-ones as potential effective chiral auxiliaries

Four new chiral 4-substituted 5,5-diethyl oxazolidin-2-ones (5a-5d) as potential effective chiral auxiliaries were synthesized from readily available amino acids via asymmetric etherification, Boc protection, Grignard reaction and cyclization reactions in four steps with overall yields of 50-60%.

Discovery of potent and selective phenylalanine based dipeptidyl peptidase IV inhibitors

anti-Substituted beta-methylphenylalanine derived amides have been shown to be potent DPP-IV inhibitors exhibiting excellent selectivity over both DPP8 and DPP9. These are among the most potent compounds reported to date lacking an electrophilic trap. The most potent compound among these is 5-oxo-1,2,4-oxadiazole 44, which is a 3 nM DPP-IV inhibitor.

Synthesis of constrained alpha-amino acid derivatives via ring-closing olefin metathesis

Five and seven membered constrained alpha-amino acid derivatives were synthesized using ring-closing metathesis reaction as a key step.